Many solutions are routinely used in laboratories and processing facilities for preparing sample batches and other liquid mixtures, as test solutions, or as stock solvents and mobile phases. Preparing such solutions requires much time to calculate the amount of reagents and dilutants, weigh the solid reagents, measure out the volumes of liquids for dilution, and combine these solution components in the correct amounts. These prepared solutions also require test measurement to confirm that they are the proper concentration or have the correct characteristics such as pH, conductivity or turbidity for their intended use. During the solution preparation and testing, the technician or scientist can be exposed to harmful chemicals and vapors that can damage their health. If a mistake is made during any of these steps, the preparer must start from the beginning, wasting the time and materials used for the solution preparation. Furthermore, the time spent making these solutions detracts from more valuable research and other duties personnel could be engaged in.
Different attempts have been made to automate this solution preparation process, such as U.S. Pat. No. 4,830,508 to Higuchi et al., but they have not fully automated a solution preparation process involving multiple solid reagents and liquid components in an accurate enough manner from multiple reagents to prepare solutions for a full range of laboratory and facilities uses. One such automated apparatus disclosed by Legrand and Bolla in “A fully automatic apparatus for chemical reactions on a laboratory scale”, J. Automatic Chem., March 1985, is a custom laboratory device to be used when it is impractical to scale up a bench-top reaction. Such a custom device is used for running a chemical reaction, and is not intended to or capable of performing all the solution preparation tasks in the automated manner and at the scale of the present invention. Other devices have been devised to measure out liquids or premixed solutions to obtain specific concentrations or dilutions, but such devices still require the initial manual preparation of solutions that include solid reagents, which are then further diluted, such as that disclosed in U.S. Pat. No. 5,833,364 to Rushing et al., U.S. Pat. No. 5,402,834 to Levin et al., U.S. Pat. No. 4,415,446 to Osborn, and the Chem+Mix™ automated solution Preparation System marketed by CHATA. Device that measure out solids to form a solution are known in relation to the cleaning industries where concentrated wash solutions are prepared by adding detergents to a solvent, such as that disclosed in U.S. Pat. No. 4,964,185 to Lehn and U.S. Pat. No. 5,607,651 to Thomas et al., and in the paint and pigment industries where solid materials are metered out and blended with liquid components, such as in U.S. Pat. No. 6,827,478 to Becker et al. These devices, however, lack the features of the present invention that facilitate the accurate preparation of laboratory solutions. Similarly, other devices may measure out a specific amount of reagent or solution, but do not combine multiple components to form a solution or monitor and adjust the characteristics of the solution being prepared. Other device prepare multiple reaction solutions for screening reactions and products in chemical and biochemical laboratories, such as in U.S. Pat. No. 7,361,309 to Vann, U.S. Pat. No. 4,476,999 to Bilbery, and U.S. Patent Application Publication 2005/0047964 to Nishida et al. These devices dispense liquid reagents, but do not weigh out solid reagents to prepare a solution. The Accelerator™ SLT100/106/112 marketed by Chemspeed Technologies® prepares small amounts of reaction solutions from solids and liquids, and conducts reactions, but lacks the features necessary to produce larger amounts of laboratory solutions.